OBD-I Codes List

Ford 581 Power to fan circuit over current

Make
Ford (1981-1995)
Category
Powertrain - Computer and Auxiliary Controls
Severity
Check Engine Light

How to read it

Code 581 reads as 5 flashes, pause, 8 flashes, pause, 1 flash on the check-engine light. Jumper the self-test input to signal return at the test connector, then run the key on engine off self test and the running self test, counting the check-engine flashes each time.

New to flash codes? The How to Read Ford EEC-IV Self-Test Codes walks through the test and what the numbers mean. The general OBD-I guide covers the rest.

What does Ford code 581 mean?

Power to fan circuit over current

Common causes of 581

  • Wiring short circuit to ground
  • Engine coolant blower motor
  • Variable control relay module
  • ECM

How to fix 581

  1. Check the circuit wiring for a short to ground
  2. Check the cooling system: level, thermostat and circulation
  3. Test the variable control relay module and replace it only if it fails its own test
  4. Test the ECM last, only after every circuit test has passed
  5. Clear the code, then retest to confirm the fix holds

Source

Source review recorded

Sources and review

Review: checked against the recorded source material.

Last updated 2026-09-29.

Report a correction for 581. Include your vehicle, the issue and a source if you have one.